Fire, pastoral farming and exotic species have been major drivers of vegetation change in the eastern South Island high country since human arrival. More recently, fire frequency and grazing intensity have declined allowing regeneration of previously suppressed woody elements in some areas, such as our 1775 ha Cass study site. We collected vegetation and abiotic data from 117 Recce plots (10 × 10 m) using an objective grid-based network to classify the vegetation, determine factors influencing vegetation pattern, discuss long-term vegetation changes and assess the role of exotic species.
Succession from anthropogenic grassland to secondary woody plant communities in New Zealand’s eastern South Island dryland zone has potential to alter animal communities. We compared indigenous and exotic birds, terrestrial invertebrates and ground-dwelling lizards in 100-ha blocks representing vegetation at three woodiness levels (grassland, mixed grassland–shrubland, and shrubland) at three sites in Central Otago.
In this paper we document the role of Phormium tenax as a nurse plant in unimproved pasture. We show that for our study area the regeneration of woody species was limited solely to P. tenax clumps with 22 native and one introduced regenerating woody species present. The number of woody species and of individual woody plants regenerating within P. tenax is not correlated with distance from the edge of the remnant forest but is significantly correlated with P. tenax clump area. P.
Relationships between composition of secondary vegetation and environment were studied in central North Island, New Zealand. A classification procedure was used to identify broad compositional groups which included forest, broadleaved scrub, shrub-fernland, sclerophyllous scrub and shrubland, and tussock-shrubland. Generalised additive models (GAMs) were used to examine relationships between species' distributions and mean annual temperature and rainfall, stand age, distance from intact forest, slope, topography, and drainage.
Natural regeneration of new forests has significant potential to mitigate greenhouse gas emissions, but how strong is the potential biodiversity co-benefit? We quantified carbon accumulation and biodiversity gain during secondary succession of two New Zealand lowland forests. The rate of carbon sequestration was the same for the kanuka–red beech succession as for the coastal broadleaved succession (c. 2.3 Mg C ha–1 year–1) over the first 50 years of succession.